1. Field of the Invention
The present invention relates to indicator light devices, and more particularly to power management of a system of indicator light devices.
2. Description of Related Art
Indicator lights are used in a variety of different types of systems for indicating a condition existing in a physical space associated with and in physical proximity to the indicator light. Indicator lights are commonly employed, for example, in smart parking systems. Smart parking systems have become popular in Asia, Europe and most recently in the United States. These systems are typically used in enclosed parking structures such as parking ramps to maximize parking utilization and increase revenue for the operator (a ramp operator, for example), and to improve the user's (a retail customer, for example) experience. One type of smart parking system uses a vehicle sensor and an indicator, typically an LED light, in proximity to each parking spot to direct customers to specific available parking spaces. A continuous green light typically indicates “available” while a continuous red light typically indicates “occupied.” An example of such a smart parking system which uses a wireless network is disclosed in US Patent Application Publication No. 2007/0050240 published Mar. 1, 2007 in the name of Belani et al.
Other examples of systems that employ indicator lights are the pick systems and the pick-put systems common in warehouses and manufacturing facilities. An example of a pick-put system is disclosed in U.S. Pat. No. 6,775,588 issued Aug. 10, 2004 to Peck. In this system, each of the various storage bays in a storage facility include a pick controller and intelligent light assemblies for each location on the bay, and a cart includes a put controller and intelligent light assemblies adjacent to specific receptacles located on the cart. A portable computer on the cart translates warehouse locations to light addresses of locations on a storage bay for indicating to the user (a worker, for example) the need for and quantity of an item to be retrieved from the illuminated location, and communicating instructions to intelligent light assemblies adjacent to specific receptacles located on the cart to indicate to the user the quantity of the retrieved item to be deposited into a particular one of the receptacles on the cart.